The initial research in this proposal will define and compare the molecular effect of the juvenile hormone mimics (Altosid TM and Altosar TM) with juvenile hormone on the insect vitellogenic system. Such a study will determine the mechanism of action (i.e., mode of action at the level of translation and/or transcription) for the mimic in insects and will indicate certain guidelines to be followed when other tissues are studied. Once we have defined the effects of Altosid TM and Altosar TM on the insect vitellogenic system, the program will center on the specific molecular events which are regulated by these mimics in crustaceans. This research will include dose-time responses of the molecular event in at least two different crustaceans (Balanus galeatus and Rhithropanopeus harrisii). The resulting data will indicate if the response is physiological or toxic and will indicate the critical levels which can be tolerated in nature. Positive evidence (i.e., mimic stimulation of transcription in crustaceans) will provide an emphasis to the research in Section III, which involved testing these mimics on frog embryos and on a sensitive mammalian cell line (HeLa cells). Such a cell line is of course not typical of the tissue which may come in contact with Altosid TM and/or Altosar TM; but it will allow us to determine if there is an universal effect of the mimic when it comes in direct contact with a susceptible cell.